FR2812507A1 - REAL-TIME DATA TRANSMISSION METHOD AND TELECOMMUNICATION NETWORK IMPLEMENTING THE METHOD - Google Patents

Abstract

The invention concerns a method for real time packet-like data transmission between a network and at least a mobile radio communication terminal, the transmission being carried out on a plurality of multiframes each comprising a specific number of blocks. The method is characterised in that it consists in dynamically allocating or assigning to the terminal or to each terminal concerned, in uplink and/or downlink transmission(s), one or more specific blocks for signalling and/or control, independently and separately from the blocks allocated to data transfer.

Description

Real-time data transmission method and network

  The present invention relates to the field of communication management in cellular radiocommunication networks, in particular downlink transmissions to mobile stations or terminals forming part of these

  networks and uplink transmissions from said mobiles to said networks.

  The subject of the present invention is a method of transmitting data in real time in packets, more precisely a method of transmitting data in real time with fixed allocation of control blocks, and a radiocommunication network.

  cell using this method.

  Here, the term "uplink" is used to denote a transmission or a transmission channel from one or more mobile terminals to the network ("uplink") and the term "downlink" to denote a transmission or a transmission channel. transmission from the network (or from a base station thereof) to one or more

  mobile devices affiliated with it ("downlink").

  Currently, in the context of the transmission of information in packets, for example according to the standards known under the designations G.P.R.S. (for "General Packet Radio Service"), E.G.P.R.S. (for "Enhanced General Packet Radio Service") and G.E.R.A.N. (for "GSM / EDGE / Radio Access Network"), no measures are planned to ensure the conservation of a constant bit rate, necessary for real-time transmission flows, between mobile or portable stations and the network when '' a message or signaling or control data must be transmitted, in

  any of the directions of transmission.

  Thus, for the G.E.R.A.N. standard, the signaling messages and the RLC user data blocks (for "Radio Link Control") are multiplexed on the same physical resource in uplink transmission and in downlink transmission. A PT indicator present in the MAC header (for "Medium Access Control") for each block received is read to determine the type of said block, ie block of user data or signaling and / or control block. This solution does not make it possible to satisfy the essential condition necessary for a transmission in real time, namely the absence of variation in the routing times, since each signaling message transmitted on an uplink or downlink radio resource shared with the blocks of user data will disrupt real-time transmission -2 and adversely affect the quality of the communication link, due to

the induced delay variation.

  The present invention aims to overcome the aforementioned drawbacks and to propose a solution allowing the transmission of signaling messages without disturbing the real-time transmission. To this end, the present invention provides a method of transmitting data in real time, in packets, between a network and at least one mobile radiocommunication terminal, the transmission being carried out on a plurality of multiframes each comprising a given number of blocks, characterized in that it consists in dynamically allocating or assigning to the terminal or to each terminal considered, in uplink and / or downlink transmission (s), one or more specific block (s) for signaling and / or independent and separate control of allocated blocks

data transfer.

  In accordance with a preferred embodiment of the invention, provision may be made to operate a fixed allocation of blocks on a multiframe or a set of multiframes, for the entire duration of a communication (composed of several bidirectional transmissions between the terminal and network) or a sequence of

  given transmission (part of a communication).

  As a variant, or in addition to the above-mentioned provisions, the network can dynamically reallocate the specific block (s) allocated to signaling and / or control, during a communication

  or during a given transmission sequence of a communication.

  According to a first variant of the invention, the allocation of control blocks associated with packet transmission consists in allocating a block per multiframe, identified by its number in this multiframe, in uplink and / or downlink transmission (s),

  on the same time interval ("timeslot"), or not, as the traffic channel.

  According to a second variant of the invention, the allocation of one or more control blocks associated with the packet transmission, is carried out by indicating a multiframe number and one or more number (s) of block (s) in this multiframe, in uplink and / or downlink transmission (s), over the same time interval, or not,

than the traffic channel.

  In the case of a sharing of the control channel between several mobile terminals, an indicator or an identification field is provided in the control block, making it possible to know the transmitting or receiving mobile station of the different signaling blocks transmitted in a multiplexed manner on said channel, this in transmission (s)

up and / or down.

  -3 - However, in downlink transmission, the control blocks transmitted from the network to a given mobile terminal can, as a variant, integrate an identifier making it possible to know the mobile terminal receiving the block containing said message.

signaling or control.

  The above method is described below in more detail, by way of nonlimiting example, in relation to a transmission method based on the standard known under the

designation G.E.R.A.N.

  In this application, the solution proposed by the invention consists in allocating a fixed allocation of the control channel associated with packet transmission (PACCH) in a multiframe 52 or in a set of multiframes 52 for uplink and downlink traffic, by l indication of a block number or a block number and a multiframe number, on the same time interval or "timeslot" as the channel

  traffic or on a different time interval than said traffic channel.

  Thus, the control blocks and the RLC data blocks are not multiplexed on the same physical resource, neither in downlink transmission, nor in

uplink transmission.

  When in downlink transmission, the fixed control channel associated with packet transmission on the downlink (DL FPACCH: "DownLink Fixed Packet Associated Control CHannel") is shared between several mobile terminals, the identification of the destination mobile terminal is given by a TFI indicator (for "Temporary Flow lentifier": identifier in temporary flow; identifies the membership of the block in a temporary flow by blocks) in the RLC / MAC control block or an identifier

  included in the signaling message.

  When in uplink transmission, the fixed control channel associated with packet transmission on the uplink (UL FPACCH: "UpLink Fixed Packet Associated Control CHannel) is shared between several mobile terminals, the identification

  of the source mobile terminal is given by a TFI indicator in the RLC data block.

  It will be noted that the implementation of the method according to the invention on a network

  existing is relatively easy and involves only minor modifications.

  The invention also relates to a cellular radio telecommunication network comprising a plurality of fixed stations distributed geographically and a plurality of mobile terminals which can be put into communication with each other for an uplink transmission from the mobiles to the network and / or a downlink transmission from the network to the mobile, said data transmissions being carried out in real time in packets over a plurality of multiframes each formed of a number

  given blocks and which can each be shared between several mobile terminals.

  -4- This network is characterized in that each terminal is (are) allocated (s) or allocated (s), in uplink and / or downlink transmission (s), one or more specific block (s) for signaling and / or control, independently and separately from allocated blocks

data transfer.

  Preferably, the allocation or allocation of specific blocks for the

  signaling and / or control is carried out as described above.

  Finally, the invention also relates to a mobile terminal for

  cellular radiocommunication, possibly part of a network of the type defined above

  above, characterized in that it is suitable for implementing the method of

  real-time data transmission as previously described.

  Of course, the invention is not limited to the embodiments described.

  Modifications remain possible, in particular from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the

  protection field of the invention.

-5 -

Claims (11)

  1. A method of transmitting data in real time, in packets, between a network and at least one mobile radiocommunication terminal, the transmission being carried out on a plurality of multiframes each comprising a given number of blocks, method characterized in that it consists in dynamically allocating or assigning to the terminal or to each terminal considered, in uplink and / or downlink transmission (s), one or more specific block (s) for signaling and / or control, independently and   separately from the blocks allocated for data transfer.   2. Method according to claim 1, characterized in that it consists in operating, for said transmission of the signaling and / or control messages, a fixed allocation of blocks on a multiframe or a set of multiframes, this for the entire duration   of a given communication or transmission sequence.   3. Method according to any one of claims 1 and 2, characterized in   that the network reallocates the specific block (s) allocated to signaling and / or control, during a communication or during a   given transmission sequence of a communication.   4. Method according to any one of claims 1 to 3, characterized in   that the allocation of control blocks associated with packet transmission consists in allocating a block by multiframe, identified by its number in this multiframe, in uplink and / or downlink transmission (s), over the same time interval, or no, than the traffic channel.   5. Method according to any one of claims 1 to 3, characterized in   that the allocation of one or more control blocks associated with the packet transmission, is carried out by indicating a multiframe number and one or more block number (s) in this multiframe, in uplink transmission (s) and / or   downlink, over the same time interval or not, as the traffic channel.   6. Method according to any one of claims 2 to 5, characterized in   what, in the case of a sharing of the control channel between several mobile terminals, an indicator or an identification field is provided in the control block, making it possible to know the mobile station transmitting or receiving the different signaling blocks transmitted multiplexed on said channel, this in transmission (s) up and / or down.   7. Method according to any one of claims 2 to 5, characterized in   that, in downlink transmission and in the case of a sharing of the control channel between several mobile stations, the control blocks transmitted from the network to a given mobile terminal -6- include an identifier making it possible to know the mobile terminal   recipient of the block containing said signaling or control message.   8. Method according to any one of claims 1 to 7, characterized in   that the transmission is carried out according to the standard known by the designation G.E.R.A.N.   9. Cellular radio telecommunication network comprising a plurality of fixed stations distributed geographically and a plurality of mobile terminals which can be put into communication with each other for an uplink transmission from the mobiles to the network and / or a downlink transmission from the network to the mobiles, said transmissions of data taking place in real time in packets on a plurality of multiframes each formed by a given number of blocks and which can each be shared between several mobile terminals, characterized in that each terminal is (are) allocated (s) or assigned, in uplink and / or downlink transmission (s), one or more specific block (s) for signaling and / or control, independently and   separately from the blocks allocated for data transfer.   10. Network according to claim 9, characterized in that the allocation or allocation of specific blocks for signaling and / or control is carried out according to   any one of claims 2 to 8.   11. Mobile cellular radiocommunication terminal, making   possibly part of a network according to any one of claims 9 and 10,   characterized in that it is suitable for implementing the transmission method of   real-time data according to any of claims 1 to 8.